Electronic sensor arrays are finding increased use for detecting analytes in fluids, such as gases or liquids. In particular, arrays of sensors based on field effect transistors are finding use in detecting ionic components, such as various cations, anions, or pH. Such sensors are often referred to as ion-sensitive field effect transistors (ISFETs).
Recently, such sensor arrays have found use in sequencing polynucleotides. Nucleotide addition results in the release of ionic species that influence the pH of a local environment. Sensors of the sensor arrays are used to detect changes in pH resulting from the nucleotide addition in the local environment. However, the pH of the local environment can be influenced by adjacent environments, referred to as crosstalk, and can be influenced by the interaction of various materials with hydrogen ions, referred to as buffering, leading to lower accuracy and less sensitivity to the changes caused by nucleotide addition.
As such, an improved sensor array would be desirable.